Magnetically activated door switch



Nov. 10, 1970 s. w. VOLAND 5 MAGNETICALLY ACTIVATED DQOR SWITCH OriginalFiled Oct. 31, 1966 V 3 l 22 I g [o g 0 9 .v I I. y,

IF I 6 3 /VENTOR ELMO W. VOLAND ATTORNEY -United States Patent Office3,539,741 MAGNETICALLY ACTIVATED DOOR SWITCH Elmo W. Voland,Indianapolis, Ind., assignor to P. R. Mallory & Co. Inc., Indianapolis,Ind., a corporation of Delaware Continuation of application Ser. No.590,732, Oct. 31, 1966. This application Aug. 8, 1969, Ser. No. 849,603Int. Cl. H0111 3/16 U.S. Cl. ZOO-61.62 4 Claims ABSTRACT OF THEDISCLOSURE This is a continuation of application Ser. No. 590,732, filedOct. 31, 1966.

This invention relates to a door switch; more particularly it relates tosuch a switch which is magnetically operated.

Various types of electrical switches are commonly used in conjunctionwith doors to actuate other devices when such doors are opened andclosed. Automobile and refrigerator doors, for example, actuate a switchwhich turns lights on and off as the door opens and closes. In suchapplications, the switch is usually actuated by a plunger protrudingthrough the door casing, the plunger being depressed upon the doorsclosing. While such an arrangement is for the most part satisfactory, itwould be better for the sake of reliability and for ease in cleaningthat the switch be actuated without the use of the protruding plunger.

It is, therefore, an object of the invention to provide a door switchwhich operates without the use of a plunger protruding from the doorscasing.

Another object of the invention is to provide a door switch which ismagnetically operated.

Another object of the invention is to provide a magnetically operateddoor switch which has a magnet disposed in the door casing and in thecompartment casing in spaced relation.

Still another object of the invention is to provide a magneticallyoperated door switch in which the switch magnet is situated at one endof a leaf spring, the other end of the spring being biased at one of thecontacts of a unitarily constructed electrical spade terminal with anelectrical contact centrally located in the leaf spring and in spacedrelationship with the other contact of the spade terminal.

Yet another object of the invention is to provide a magneticallyoperated door switch/.which is simple in construction, reliable, andeconomic to produce.

In the drawings:

FIG. 1 is an exploded view in partial cross section of the switch andits actuating means;

FIG. 2 is a cross section taken along line 22 of FIG. 1; and

FIG. 3 is a partial cross section of the switch and its actuating meanswhen the door is in the closed position.

Generally speaking, the objects of the invention are accomplished byproviding a magnetically operated door switch that is located in thecasing of the compartment utilizing the door, the actuating means forthe switch being located in the door casing. More specifically, themagnetic switch comprises a housing disposed within the casing of anopening for a compartment, a leaf spring dis- 3,539,741 Patented Nov.10, 1970 posed within the housing, the spring being at one end fixedlyconnected to the housing and further at the same end being in electricalcontact with an electrical contact of an electrical spade terminal, amagnet disposed at the other end of the spring and being in spacedalignment with a magnet of opposite polarity disposed within the casingof a door adapted to close the opening of the compartment, and anelectrical contact centrally disposed on the leaf spring and being inspaced alignment with the other electrical contact of the spadeterminal.

Referring now to FIGS. 1 and 2 the novel magnetic switch 10 is heldwithin the casing 11 defining the opening of a compartment. The termcompartment is here meant to mean any enclosed space, whether it be arefrigerator storage area, the passenger space of an automobile, or asimple storage box. The switch 10 has a housing 12, the housing as wellas the casing being made from an insulating material such as athermosetting plastic. Disposed within the housing is a leaf spring 13that is fixedly connected to the housing at one end through a rivet orother pin type connection 14. The pin also serves as an electricalconnection between the leaf spring and one of the electrical terminals15 of a unitarily constructed spade terminal 16, the pin 14 also servingto attach the terminal to housing 12.

Attached to the leaf spring at its opposite end is a magnet 17 that isconstructed of a suitable magnetic material such as iron, a ceramic-ironmixture, or the like. Centrally disposed on the spring is an electricalcontact 18 which is in spaced alignment with an electrical contact 19.Electrical contact 19 is in electrical contact with terminal 20 of spadeterminal 16 through rivet or pin 21, the pin also serving to attachcontact 19 and terminal 20 to the housing 12.

The means to actuate the switch is disposed within the door 22. Themeans to actuate the switch comprises a magnet 23 disposed within thecasing 24 of the door. Casing 24 is preferably constructed of anelectrically insulating material such as a plastic or rubber moulding.Magnet 23 can be fabricated from a material similar to magnet 17;however its pole should be opposite that of magnet 17. With thisactuating structure, there need be no plunger protruding from the doorcasing as is common in prior art door switches. As an alternative, thecasing 24 could be constructed of a plastic or rubber materialimpregnated with a magnetic material, thus eliminating the need formagnet 23.

Referring to FIGS. 1 and 3, the operation of the switch can be shown asthe door is opened or closed. As shown in FIG. 1, when the door isopened, contact 18 is closed with contact 19, thus completing theelectrical circuit through the spade terminal 16, the spring beingbiased such that the circuit is closed when the door is open. Thus alight or other device within the compartment will be ON when the door isopen. When the door is closed, as is shown in FIG. 3, magnet 23 attractsmagnet 17, thus causing the circuit through the spade terminal 16, andleaf spring 13 to be opened when contact 18 disengages contact 19. Thelight is then turned OFF. It should be understood that it is within thescope of the invention that the spring may be oppositely biased with thepolarity of the magnets being reversed.

FIG. 3 also shows an alternate form of the invention wherein the leafspring is constructed to give a snap action. In this embodiment leafspring 13 has a circular depression or dimple 25 located near the endwhere it is fixedly connected to the housing 12 such that a snappingaction is imparted to the spring when the spring is released throughseparation of the magnets.

From the foregoing discription it will be apparent to those skilled inthe art that this invention provides a new and useful door switch.Accordingly, it is contemplated that the scope of the invention is to bedetermined from the claims appended hereto.

What is claimed is:

1. A combination comprising: a door switch comprising a housing ofelectrically insulating material disposed within a casing ofelectrically insulating material forming the opening of a compartment, aleaf spring disposed within said housing fixedly connected to saidhousing at one end thereof, a magnet disposed at the other end of saidleaf spring, a first electrical contact centrally disposed on said leafspring, a second contact carried by said housing in line with said firstcontact; a second magnet of opposite polarity from said first magnetcarried by a door connected to said compartment closing said opening;said leaf spring biased to close said contacts when said door is open;and means to complete an electrical circuit through said leaf spring andelectrical terminals connected to said switch.

2. A door switch according to claim 1 in which said leaf spring has acircular depression near its end where it is fixedly connected to saidhousing so as to impart a snapping action to said spring.

References Cited UNITED STATES PATENTS 186,169 1/1877 Rowbotham.2,924,682 2/ 1960 Winterburn 3 35205 2,448,779 9/ 1948 Crise 3 35-2053,017,473 1/196-2 Verger 340274 XR 3,222,473 12/ 1965 Delhase ZOO-61. 62

ROBERT K. SCHAEFER, Primary Examiner M. GINSBURG, Assistant Examiner US.Cl. X.R. 335--207

